Kirchoffs's Laws

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A little history about Kirchoff
A little history about Ohm
Kirchoff's current and voltage laws
Ohm's law
Circuit analysis example
Bibliography

A little bit about the life and times of Gustav Robert Kirchoff:

Gustav Robert Kirchoff was a German physicist born on March 12, 1824, in Konigsber, Prussia. Gustav Kirchoff's first research topic was on the conduction of electricity. As a result of this research, Kirchoff wrote the Laws of Closed Electric Circuits in 1845. These laws were eventually named after their author, which are now known as Kirchoff's Current and Voltage Laws. Because Kirchoff's Voltage and Current laws apply to all electric circuits, a firm understanding of these fundamental laws is paramount in the understanding of how an electronic circuit functions. Although these laws have immortalized Kirchoff in the field of Electrical Engineering, Kirchoff also had additional discoveries. Gustav Kirchoff was the first person to verify that an electrical impulse traveled at the speed of light. Furthermore, Kirchoff made major contributions in the study of spectroscopy and he advanced the research into blackbody radiation. Gustav Robert Kirchoff died in Berlin in October 17, 1887.

Gustav Robert Kirchoff
(1824-1887)

http://www.ece.utexas.edu/~aduley/lab/

Home Page | A little history about Kirchoff | A little history about Ohm | Kirchoff's current and voltage laws | Ohm's law | Circuit analysis example | Bibliography

Jeremie Smith
fsjds2@uaf.edu
Date Last Modified: 11/20/00

|Ohm's law|| |Home Page [->0]A little history about Kirchoff[->1]A little history about Ohm[->2]Kirchoff's current and voltage laws[->3]Ohm's lawCircuit analysis example[->4]Bibliography[->5]|It's time for the nitty-gritty. Let's define Ohm's Laws:Ohm's law can be stated in words as the current in a resistive circuit is directly proportional to its applied voltage and inversely proportional to its resistance. In equation form, Ohm's law statesV = I*RwhereV is the applied voltage, R is the resistance in Ohms,I is the current in amperes.Ohm's law demonstrates that if the applied voltage across a circuit is increased or decreased, the current generated in the circuit increases and decreases, respectively. Furthermore, as the resistance in a circuit increases, the current generated in the circuit decreases. The following are algebraic variations of Ohm's law that demonstrate theses observations.I = V / R R = V / IUsing one of the three algebraic variations of Ohm's law, and any two known variables, one can solve for the other unknown quantity. |

Home Page [->6]| A little history about Kirchoff[->7] | A little history about Ohm[->8] | Kirchoff's current and voltage laws[->9] | Ohm's law | Circuit analysis example[->10] | Bibliography[->11] Jeremie Smith

fsjds2@uaf.edu[->12]
Date Last Modified: 11/20/00

|Kirchoff's current and voltage laws|| |Home Page [->13]A little history about Kirchoff[->14]A little history about Ohm[->15]Kirchoff's current and voltage lawsOhm's law[->16]Circuit analysis example[->17]Bibliography[->18]|It's time for the nitty-gritty. Let's define Kirchoff's Current and Voltage Laws:First Kirchoff's Current Law.Kirchoff's Current law can be stated in words as the sum of all currents flowing into a node is zero. Or conversely, the sum of all currents leaving a node must be zero. As the image below demonstrates, the sum of currents Ib, Ic, and Id, must equal the total current in Ia. Current flows through wires much like water flows through pipes. If you have a definite amount of water entering a closed pipe system, the amount of water that enters the system must equal the amount of water that exists the system. The number of branching pipes does not change the net volume of water (or current in our case) in the system....

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9.1
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1. POWER PACK
POWER PACK
RESISTOR
RESISTOR
VOLTMETER
VOLTMETER
AMMETER
AMMETER
A
A
V
V
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